Presented by

Gary S. Lynn, P.E.

Vapor Leaks: Pressure’s Building

What Causes Vapor Leaks?UST Pressurization

Delivery Pressure SpikesStage II System Design and Operation

Vapor GrowthA/L Ratio > 1ORVR System Incompatibility

Leaky Components

Stage I vs Stage II Vapor RecoveryStage I - Recovering Vapors While Filling UST

Stage II - Recovering Vapors While Filling Vehicle

Courtesy Gilbarco/Veeder Root

ORVR Vehicle Tank

Vapors are routed to ORVR canister. Fill pipe diameter narrowsafter unleaded restrictor plate. This creates a liquid seal that forcesvapors into ORVR canister. It also causes an inward flow of air intothe fill pipe. There is no vapor for a vacuum assist system to recover.Vacuum assist systems return air to UST.

Leaky Components

Atmospheric LeaksPressure Vents, Dispenser Leaks, Nozzles

Subsurface LeaksDry Breaks, ATG Covers, Fill Caps, threaded connections…..

Fixing Atmospheric Leaks Promotes Subsurface Leaks

Why are Vapor Leaks Important?

Numerous Vulnerable Systems PresentStage I Systems – Most of Existing TanksStage II Systems – 45,000 USTs

Leaks are CommonNH Pressure Decay vs. MtBE Concentration Study

Suggests 75% of Stage II stations with leaks Leaks, when present, average 30ppm MtBE near UST

Why are Vapor Leaks Important?

Volatile Constituent ProblemVolatile components concentrate in vapor phase, represents high % of mass in leak

MtBE low biodegradability yields MtBE dominant sites (Lahvis API modeling, NH DES site review)

Reimbursement Fund SpendingReceptor Threats

Benzene, Ethanol high biodegradability yields DO sink?

Vapor Composition FactorLiquid/Gas Composition*

RFG Gas Composition

Vp (mm Hg)

Constituent

15 / 46.3%15%1824 to 151

Butanes, pentanes, hexanes & enes

2.2 / 5.2%18.2 / 7.8%4 / 0.6%15.4 / 2.1%

0 to 4.9%1 to 20%.2 to 4%1 to 18%

8628106.6-8.7

BenzeneTolueneEthylbenzeneXylenes

3.7 / 9.3%10 to 15%251MtBE

* Example composition from Lauri Saarinen People and Work Research Report 51. Note: Ethanol has a vapor pressure of 53 mm.

NH Studies

NH Site Data Review (MtBE only or dominant sites at approximately 30% of the NH Stage II System Equipped Sites)UST System Pressures ProfilingStage I System Vapor LeaksStage II System Pressure Reduction

-1

-0 .5

0

0 .5

1

1 .5

2

2 .5

3

3 .5

4

03/

30/0

4 1

1:29

:22

03/

30/0

4 1

9:49

:22

03/

31/0

4 0

4:09

:22

03/

31/0

4 1

2:29

:22

03/

31/0

4 2

0:49

:22

04/

01/0

4 0

5:09

:22

04/

01/0

4 1

3:29

:22

04/

01/0

4 2

1:49

:22

04/

02/0

4 0

6:09

:22

04/

02/0

4 1

4:29

:22

04/

02/0

4 2

2:49

:22

04/

03/0

4 0

7:09

:22

04/

03/0

4 1

5:29

:22

04/

03/0

4 2

3:49

:22

04/

04/0

4 0

8:09

:22

04/

04/0

4 1

6:29

:22

04/

05/0

4 0

0:49

:22

04/

05/0

4 0

9:09

:22

04/

05/0

4 1

7:29

:22

04/

08/0

4 1

4:52

:00

UST

Pres

sure

(in

wc)

Delivery Event Delivery

Event

Stage II - Balance System Pressure Profile

Plaistow Citgo, New HampshireUST pressure in inwc

-8

-6

-4

-2

0

2

4

6

8

10

07/1

4/04

12:

45:0

9

07/1

5/04

05:

25:0

9

07/1

5/04

22:

05:0

9

07/1

6/04

14:

45:0

9

07/1

7/04

07:

25:0

9

07/1

8/04

00:

05:0

9

07/1

8/04

16:

45:0

9

07/1

9/04

09:

25:0

9

07/2

0/04

02:

05:0

9

07/2

0/04

18:

45:0

9

07/2

1/04

11:

25:0

9

07/2

2/04

04:

05:0

9

07/2

2/04

20:

45:0

9

07/2

3/04

13:

25:0

9

07/2

4/04

06:

05:0

9

07/2

4/04

22:

45:0

9

07/2

5/04

15:

25:0

9

07/2

6/04

08:

05:0

9

07/2

7/04

00:

45:0

9

07/2

7/04

17:

25:0

9

07/2

8/04

10:

05:0

9

in w

c

Delivery spike

Delivery spike

Delivery Spike

O'Briens, a tighter vacuum assist systemUST pressure in inwc

-8-7.5

-7-6.5

-6-5.5

-5-4.5

-4-3.5

-3-2.5

-2-1.5

-1-0.5

00.5

11.5

22.5

33.5

44.5

04/2

2/04

07:

57:36

04/2

2/04

13:

22:21

04/2

2/04

17:

22:21

04/2

2/04

21:

22:21

04/2

3/04

01:

22:21

04/2

3/04

05:

22:21

04/2

3/04

09:

22:21

04/2

3/04

13:

22:21

04/2

3/04

17:

22:21

04/2

3/04

21:

22:21

04/2

4/04

01:

22:21

04/2

4/04

05:

22:21

04/2

4/04

09:

22:21

04/2

4/04

13:

22:21

04/2

4/04

17:

22:21

04/2

4/04

21:

22:21

04/2

5/04

01:

22:21

04/2

5/04

05:

22:21

04/2

5/04

09:

22:21

04/2

5/04

13:

22:21

04/2

5/04

17:

22:21

04/2

5/04

21:

22:21

04/2

6/04

01:

22:21

04/2

6/04

05:

22:21

04/2

6/04

09:

22:21

04/2

6/04

13:

22:21

04/2

6/04

17:

22:21

04/2

6/04

21:

22:21

04/2

7/04

01:

22:21

04/2

7/04

05:

22:21

in wc

Pressure Bleeds Out at Night

UST Pressure Builds During the Day

-8-7.5

-7-6.5

-6-5.5

-5-4.5

-4-3.5

-3-2.5

-2-1.5

-1-0.5

00.5

11.5

22.5

33.5

44.5

55.5

6

09/1

5/04

11:

16:4

509

/15/

04 1

7:56

:45

09/1

6/04

00:

36:4

509

/16/

04 0

7:16

:45

09/1

6/04

13:

56:4

509

/16/

04 2

0:36

:45

09/1

7/04

03:

16:4

509

/17/

04 0

9:56

:45

09/1

7/04

16:

36:4

509

/17/

04 2

3:16

:45

09/1

8/04

05:

56:4

509

/18/

04 1

2:36

:45

09/1

8/04

19:

16:4

509

/19/

04 0

1:56

:45

09/1

9/04

08:

36:4

509

/19/

04 1

5:16

:45

09/1

9/04

21:

56:4

509

/20/

04 0

4:36

:45

09/2

0/04

11:

16:4

509

/20/

04 1

7:56

:45

09/2

1/04

00:

36:4

509

/21/

04 0

7:16

:45

09/2

1/04

13:

56:4

509

/21/

04 2

0:36

:45

09/2

2/04

03:

16:4

509

/22/

04 0

9:56

:45

09/2

2/04

16:

36:4

509

/22/

04 2

3:16

:45

09/2

3/04

05:

56:4

509

/23/

04 1

2:36

:45

09/2

3/04

19:

16:4

509

/24/

04 0

1:56

:45

09/2

4/04

08:

36:4

509

/24/

04 1

5:16

:45

09/2

4/04

21:

56:4

509

/25/

04 0

4:36

:45

09/2

5/04

11:

16:4

509

/25/

04 1

7:56

:45

09/2

6/04

00:

36:4

509

/26/

04 0

7:16

:45

09/2

6/04

13:

56:4

509

/26/

04 2

0:36

:45

09/2

7/04

03:

16:4

509

/27/

04 0

9:56

:45

09/2

7/04

16:

36:4

509

/27/

04 2

3:16

:45

09/2

8/04

05:

56:4

5

in w

c

Delivery spike

More Delivery spikes

Leak repairs on 9/23/04

Healy ORVR Nozzle

Healy ORVR Nozzle

-8-7.5

-7-6.5

-6-5.5

-5-4.5

-4-3.5

-3-2.5

-2-1.5

-1-0.5

00.5

11.5

22.5

33.5

44.5

55.5

610

/04/

04 1

4:47

:30

10/0

4/04

21:

27:3

0

10/0

5/04

04:

07:3

010

/05/

04 1

0:47

:30

10/0

5/04

17:

27:3

0

10/0

6/04

00:

07:3

010

/06/

04 0

6:47

:30

10/0

6/04

13:

27:3

010

/06/

04 2

0:07

:30

10/0

7/04

02:

47:3

0

10/0

7/04

09:

27:3

010

/07/

04 1

6:07

:30

10/0

7/04

22:

47:3

010

/08/

04 0

5:27

:30

10/0

8/04

12:

07:3

0

10/0

8/04

18:

47:3

010

/09/

04 0

1:27

:30

10/0

9/04

08:

07:3

0

10/0

9/04

14:

47:3

0

10/0

9/04

21:

27:3

010

/10/

04 0

4:07

:30

10/1

0/04

10:

47:3

0

10/1

0/04

17:

27:3

010

/11/

04 0

0:07

:30

10/1

1/04

06:

47:3

0

10/1

1/04

13:

27:3

0

10/1

1/04

20:

07:3

010

/12/

04 0

2:47

:30

10/1

2/04

09:

27:3

0

10/1

2/04

16:

07:3

010

/12/

04 2

2:47

:30

10/1

3/04

05:

27:3

010

/13/

04 1

2:07

:30

10/1

3/04

18:

47:3

0

10/1

4/04

01:

27:3

010

/14/

04 0

8:07

:30

in wc

Delivery spike

Air to Liquid Ratio Changed Delivery Spike

Stage I Leak Study

Fremont Village Market Shallow, thin overburden aquifer (2 to 5 feet water table, 15 feet to bedrock)BTEX contamination in one well (original release)New MtBE problem impacting surrounding dug wells (2 wells with treatment systems 6 wells total impacted)MtBE at approximately 1 ppm in groundwater

Addressing the Stage I leakSVE system installed in tank gravel packVapor release during fuel deliveries observed in vapors collected by SVEVapor releases identified and repaired during subsequent inspectionRevisit to observe changes in vapor collection during deliveries pending

SVE System Shed

0

10

20

30

40

50

60

8 : 00 9: 00 1 0 :0 0 1 1 :0 0 1 2 :0 0 13 :0 0 14 : 00 1 5: 00 1 6: 00 1 7: 0 0

Ti me

Start and End of Fuel Delivery

Fremont – SVE TVOC vs. Time

Return to Background

SVE Influent Grab Sample for Fremont Site

4,910Hexane2,850Heptane

14,000Toluene

118,000MtBE

2,070Xylenes and all others

5,330Benzene

Results PPBvContaminant

Solution: SVE + Inspection & Repair

Delivery Inspection by former UST Inspector, now remedial program PMLeaks found at dry break and several ATGs

Dry break may have been bypassedLast delivery of route, 2AM deliveries

SVE operation bracketing delivery (timer set for Thursday thru Sunday)

MtBE at 41ppb versus up to 1,760 ppb prior to intervention

Fremont Site Dry Break

Dry break vapor leak

Dry Break

Scored by Screwdriver?

Fremont Site ATG Cover

Leaking Threaded Connection

Note: Gravel pack around sump

Stage II Leak Study

Waterhouse Country Store MtBE concentrations in groundwater detected above 400,000 ppbLimited BTEX in groundwaterMtBE only contaminant above soil standards5 private wells with MtBE treatment systemsDouble wall tank and piping, in complianceVacuum assist vapor recovery system/vapor release concern

Addressing the Stage II LeakProfile UST System Operating Pressures and Document Release(s)

Tank pressure monitoring w/ data loggerPraxair Enhanced TracerTight testing

Reduce Pressures with Vaporsaver Monitor Long-term Changes in MtBE Concentrations in Groundwater

Tank Pressure Monitoring

Datalogger Setup

Vent tap for pressure

monitoring

Waterhouse in WindhamUST pressure UST inwc

-5.0

-4.5

-4.0

-3.5

-3.0

-2.5

-2.0

-1.5

-1.0

-0.5

0.0

0.5

1.0

1.5

2.0

2.5

3.0

02/1

1/0

4 1

1:13

:20

02/1

2/0

4 1

8:43

:39

02/1

3/0

4 0

3:03

:39

02/1

3/0

4 1

1:23

:39

02/1

3/0

4 1

9:43

:39

02/1

4/0

4 0

4:03

:39

02/1

4/0

4 1

2:23

:39

02/1

4/0

4 2

0:43

:39

02/1

5/0

4 0

5:03

:39

02/1

5/0

4 1

3:23

:39

02/1

5/0

4 2

1:43

:39

02/1

6/0

4 0

6:03

:39

02/1

6/0

4 1

4:23

:39

02/1

6/0

4 2

2:43

:39

02/1

7/0

4 0

7:03

:39

02/1

7/0

4 1

5:23

:39

02/1

7/0

4 2

3:43

:39

02/1

8/0

4 0

8:03

:39

in w

c

OPW Vaporsaver 1 operating

UST pressure flat line at night indicates leak.

UST pressure builds during customer dispensing times, drops to atmospheric overnight

Deliveries

Vaporsaver Installation

Vaporsaver and temporary base

Custom fitting for vent withdrawal and return

Test SiteUST pressure UST inwc

-0.90

-0.80

-0.70

-0.60

-0.50

-0.40

-0.30

-0.20

-0.10

0.00

0.10

0.20

0.30

0.40

0.50

0.60

0.70

0.80

0.90

02/1

8/04

06:

00:3

9

02/1

8/04

06:

30:3

9

02/1

8/04

07:

00:3

9

02/1

8/04

07:

30:3

9

02/1

8/04

08:

00:3

9

02/1

8/04

08:

30:3

9

02/1

8/04

09:

00:3

9

02/1

8/04

09:

30:3

9

02/1

8/04

10:

00:3

9

02/1

8/04

10:

30:3

9

02/1

8/04

11:

00:3

9

02/1

8/04

11:

30:3

9

02/1

8/04

12:

00:3

9

02/1

8/04

12:

30:3

9

02/1

8/04

13:

00:3

9

02/1

8/04

13:

30:3

9

02/1

8/04

14:

00:3

9

02/1

8/04

14:

30:3

9

Vaporsaver operating: +0.10 in wc to -0.50 in wc

Data Logger removed for download.

Groundwater Data for Research Site (JB-16/MW)

65%65%31%% Reduction

225,000168,00017,000Average Initial MtBE Conc. (8 rds)

79,00059,00010,000Post Pressure MtBE Reduction (5rds)

Well JB16(ppb MtBE)

Well JB14 (ppb MtBE)

MW-JB13(ppb MtBE)

Date

Note: Vaporsaver unit operation from February ’04 to November ’05 (30% downtime). MW-JB16D also shows 65% reduction.

Unit Operational ProblemsRetrofit Problem

Only the Second Retrofit Unit Compressor Problem (recirculation?)

VoltageBelt AlignmentLoose FanOPW Working on Problems100% Reliability Needed

Lessons LearnedUST Pressurization needs to be minimizedGasoline Composition Important

MtBE and other ether problemCompounds w/ similar physical properties issue

Coordination w/ Vapor Recovery Program Essential

Subsurface/atmospheric release tradeoffStepped up inspection and repairRevision to rules, testing, hardware necessary

Solutions/Follow up Studies

UST Merged w/ Vapor Recovery ProgramMore, better coordinated inspectionsVapor Recovery Program rule changes

Monthly inspections, annual maintenanceLeak detection inspections during deliveries

Independent Oil Company PilotInspection/Maintenance implementationORVR compatible nozzlesPressure Reduction

Oil Company Pilot PilotIntensive Inspection/Repair Program

36 enhanced inspections during deliveriesTracer Testing Inspect/RepairStage II Pressure Decay Testing

Gilbarco/Veeder Root ORVR NozzleHealy ORVR Nozzle plus Bladder TankVapor System Technology/OPW VaporsaverCheap generic SVE system

UST Enhanced Inspection Program at Cumbys

By former UST Inspector, now in remedial section 13 Enhanced Inspections, 8 Regular Inspections

Enhanced Inspections during gas deliveries, pressures monitored, fittings soaped, repairs made while onsite

Findings (77 leaks or 4/gas station)Vapor Leaks: 15 Dry Breaks, 14 Fill Caps, 14 ATG covers, 6 vent covers, 4 spill bucket drains, 6 dispenser vapor leaksLiquid Leaks: 6 spill buckets, 4 product in sumps and 7 liquid releases from fittings under dispensers

Score: Enhanced Inspections 67 Regular Insp. 10

Dry Break Leaks - Epping

Corroded Dry Break

Dry Break Leaks - Keene

Dry Break Vapor Release

Dry Break Leaks - Plaistow

New, just out of box, dry break leak

Leaky ATG - Greenland

Sheen on water

Product Leaks –Newington/Milford

Sensor set above product

Gravel pack around sump

Oil Company Pilot TimelineSecure Funding (spring of 2005)

SEP NegotiationsGREE Fund MoneyEPA Funding Application

Complete Delivery Inspections (end of 04)Baseline groundwater contamination (diffusion bags) spring 2005Installation of hardware (summer 2005)

Instrument Gas Station (pressures, soil temps. Etc)

Contact Information

Gary Lynn, P.E. Office: 603 271-8873E-mail: glynn@des.state.nh.us

Mail: New Hampshire Department of Environmental Services

29 Hazen DriveConcord, New Hampshire 03304